Bad error message for string type PIT key

[Tom-Newton]

When leftPitKey or rightPitKey is a string type codegen compilation fails

24/02/07 13:43:25 ERROR CodeGenerator: failed to compile: org.codehaus.commons.compiler.CompileException: File 'generated.java', Line 68, Column 50: A method named "clone" is not declared in any enclosing class nor any supertype, nor through a static import
org.codehaus.commons.compiler.CompileException: File 'generated.java', Line 68, Column 50: A method named "clone" is not declared in any enclosing class nor any supertype, nor through a static import

Probably this should be explicitly disallowed.